This study aimed to investigate the role of oxidative metabolism in resistant (UFSC-01) and susceptible (Uirapuru) bean genotypes against Colletotrichum lindemuthianum (Cl) and its association with ...phenotypic resistance. Anthracnose severity levels were higher and more varied in susceptible compared to resistant plants. Only UFSC-01 inoculated with Cl exhibited atypical lesions. Cl was detected in symptomatic and asymptomatic tissues of cultivar (cv.) Uirapuru, as well as atypical lesions and asymptomatic tissues of UFSC-01, suggesting that the pathogen can survive and grow without causing any visible symptoms. The activities of guaiacol peroxidase, superoxide dismutase, and ascorbate peroxidase enzymes was significantly higher in Cl-inoculated UFSC-01 compared to the susceptible genotype. There was no change in catalase activity observed in either genotype. After inoculation with Cl, the content of hydrogen peroxide decreased only in cv. Uirapuru, while the amount of malondialdehyde, an indicator of lipidic peroxidation in cells, was found to be higher exclusively in UFSC-01 compared to the other treatments. Our findings suggest that increased enzymes activity and accumulation of molecules involved in oxidative metabolism play a significant role in the defense mechanisms leading to resistance of beans against Cl. These mechanisms can result in cell damage, hypersensitivity response, and atypical lesions in the resistant genotype.
•Increased enzyme activities and oxidative metabolism play key roles in bean resistance to Colletotrichum lindemuthianum.•The activities of GPX, SOD, and APX enzymes were higher in the resistant genotype after inoculation with C. lindemuthianum.•The content of hydrogen peroxide decreased in susceptible plants infected with C. lindemuthianum.•Lipid peroxidation was higher after inoculation of resistant plants.•Resistant bean genotypes exhibit atypical lesions and hypersensitivity responses to C. lindemuthianum infection.
Background: The present study is region specific carried out to see the relation of bean anthracnose with weather in Kashmir and also to assess the yield loss in bean vis-à-vis anthracnose. Such ...studies form basis for deciding disease suppressive crop geometry and also sowing date alterations besides helping in disease predictions. The yield loss study in particular reveals the importance of a disease before any management strategies are worked out.
Methods: Epidemiology was conducted under natural epiphytotic conditions using a susceptible bean cv. Shalimar Rajmash-1 for recording disease development at weekly intervals. Yield loss assessment was also recorded on Shalimar Rajmash-1 where different disease levels were created by inoculating at different phonological stages after maturity the crop stand disease free.
Conclusion: During cropping season, the incidence and intensity of bean anthracnose developed to the extent of 77.06 and 54.51 per cent, when average temperature, average RH and weekly rain fall ranged from 16.6-23.8oC, 62.2-76.5 per cent and 1.7-48.2 mm, respectively. However, the highest periodic increase in disease incidence (12.62%) was recorded during 24th standard metrological week which coincided with highest rain fall and the increase in periodic disease intensity was higher ( greater than 10%) when RH was above 70 per cent. The yield loss in bean vis-a-vis variable levels of disease as created by inoculating different unit population of bean plants at different phenological stages revealed significant and positive correlation of bean anthracnose and yield loss. Highest yield loss (68.42%) was recorded in populations where the disease started at 1st trifoliate stage which then reached maximum intensity of 81.09 per cent at physiological maturity. The terminal disease intensity in population where disease started at pod filling was significantly low (18.59%) and caused least yield loss of 10.95 per cent. The study reveals that bean anthracnose caused significant yield loss when it appeared at any stage upto flowering.
Twelve genotypes of common bean were evaluated against anthracnose under natural epiphytotic conditions. This study was carried out in a randomized complete block design with three replications at ...the research field of Agriculture Research Station (ARS), Vijaynagar, Jumla, Nepal from June to September 2018. The area under the disease progress curve (AUDPC) and disease severity were calculated. In laboratory conditions, artificial inoculation was carried out on detached leaves of twelve genotypes using a pure culture suspension of Colletotrichum lindemuthianum (1.2× 106 conidia ml–1) in a completely randomized design with three replications. The results showed that bean genotypes varied significantly for disease severity both in the field and laboratory conditions. In the field, bean genotypes showed resistance to highly susceptible reactions. Their AUDPC value ranged from 120.55 to 502.31. The lowest mean AUDPC value was recorded in KBL-1 (120.55) followed by KBL-3 (123.79) and KBL-2 (124.44). Similarly, the lowest severity value was recorded with KBL-1 (0.51), KBL-2 (0.52) and KBL-3 (0.53). Detached leaf assay in laboratory experiment showed that the lowest mean AUDPC was found in KBL-2 (16.67) and KBL-3 (16.67). Therefore, KBL-2 and KBL-3 could be utilized as resistant varieties to anthracnose disease under Jumla and similar field conditions.
Anthracnose, caused by the fungus
, is a major disease of common bean (
L.) worldwide.
is genetically highly variable, and understanding the pathogen's diversity and distribution is a key step in ...developing common bean varieties with durable anthracnose resistance. The objectives of this study were to (i) characterize the race structure of
in Zambia and (ii) assess the molecular diversity of
in Zambia. A field survey was conducted in 20 bean-growing districts in Zambia to collect anthracnose symptomatic bean plants. A total of 103
isolates were collected and characterized based on their reactions on 12 common bean race differential cultivars. RAM and ERIC-BOX DNA markers were used to assess molecular diversity of 60 isolates. A total of 58 races were characterized from the 103 isolates. Race 5 was the least virulent, and race 1631 was the most virulent based on their reaction on the 12 race differential cultivars. Race 19 had the highest recovery frequency (11%) and was the most extensively dispersed among the 22 bean-growing districts from where the isolates were collected. Only six races had previously been reported in Zambia, and 52 races were identified as new races reported for the first time in Zambia. Two races were virulent only on Andean cultivars, 11 races were virulent only on Middle American cultivars, and 45 races were virulent on both Andean and Middle American cultivars. No individual isolate showed pathogenicity on all the differential cultivars, and no isolate overcame the
,
, and
resistance gene pyramid that naturally exists in G2333. Phylogenetic analysis categorized the 60 isolates in six major clusters and six subclusters. The 60 isolates showed high genetic heterogeneity among and within a race of the same virulence. The study has revealed the existence of both Andean and Middle American races and extensive molecular diversity of
in Zambia. The knowledge on the race structure of
that this study has provided will be valuable for making breeding decisions on the host plant resistance genes required for developing common bean varieties with durable resistance to anthracnose in Zambia.
El frijol común (Phaseolus vulgaris L.) es el segundo grano más importante cultivado en Guatemala y es la principal fuente de proteína de origen vegetal para el guatemalteco. El cultivo se ve ...afectado por la antracnosis, una enfermedad causada por el patógeno Colletotrichum lindemuthianum, un hongo que puede afectar el rendimiento del grano, hasta un 100%. El Instituto de Ciencia y Tecnología Agrícolas (ICTA) cuenta con una colección de frijol arbustivo de la región del altiplano del país, la cual ha presentado resistencia bajo presión natural de la enfermedad. Sin embargo, no se había evaluado con razas de C. lindemuthianum previamente reportadas. El programa de mejoramiento de frijol en Guatemala necesita identificar fuentes de resistencia a razas del patógeno que se han reportado en la zona, esto es posible cuando se dispone de un germoplasma diverso. En este proyecto se identificaron fuentes de resistencia a antracnosis utilizando como inóculo aislamientos de las razas del patógeno 585 y 3981, e inoculadas a 216 accesiones de la colección de frijoles arbustivos. En total, el 10% de las accesiones resultaron resistentes (escala 1-3) a ambas razas del patógeno evaluando su severidad con base en una escala visual estándar de 1 a 9. Las fuentes de resistencia encontradas en frijol para C. lindemuthianum pueden ser utilizadas en el programa de mejoramiento de frijol en Guatemala o a nivel mundial.
The substitution of landrace populations of beans ('Phaseolus vulgaris' L.) by commercial cultivars provided genetic uniformity and loss of rusticity. It makes the bean plants more vulnerable to ...pests, increasing the use of pesticides. The objective of this work was to evaluate the productivity and health of beans landraces compared to commercial cultivars, reducing the effect of high dynamic dilutions. The evaluated traits were grain yield (kg ha-1), thousand grain weight (g), and occurrence of anthracnose ('Colletotrichum lindemuthianum') and bacteriosis ('Xanthomonas' sp.). Evaluation of high dynamic dilutions was also done in addition to the previous variables, was evaluated number of pods per plant and pods with the presence of anthracnose. The analysis of the data did not show any differences in the productivity and disease rate between the landraces and the commercial cultivars of beans. The high dynamic dilutions do not show any conclusive results in terms of productivity. However, all treatments were superior in phytosanitary management compared to control.
Anthracnose is a seed-borne disease of common bean (Phaseolus vulgaris L.) caused by the fungus Colletotrichum lindemuthianum, and the pathogen is cosmopolitan in distribution. The objectives of this ...study were to identify new sources of anthracnose resistance in a diverse panel of 230 Andean beans comprised of multiple seed types and market classes from the Americas, Africa, and Europe, and explore the genetic basis of this resistance using genome-wide association mapping analysis (GWAS). Twenty-eight of the 230 lines tested were resistant to six out of the eight races screened, but only one cultivar Uyole98 was resistant to all eight races (7, 39, 55, 65, 73, 109, 2047, and 3481) included in the study. Outputs from the GWAS indicated major quantitative trait loci (QTL) for resistance on chromosomes, Pv01, Pv02, and Pv04 and two minor QTL on Pv10 and Pv11. Candidate genes associated with the significant SNPs were detected on all five chromosomes. An independent QTL study was conducted to confirm the physical location of the Co-1 locus identified on Pv01 in an F4:6 recombinant inbred line (RIL) population. Resistance was determined to be conditioned by the single dominant gene Co-1 that mapped between 50.16 and 50.30 Mb on Pv01, and an InDel marker (NDSU_IND_1_50.2219) tightly linked to the gene was developed. The information reported will provide breeders with new and diverse sources of resistance and genomic regions to target in the development of anthracnose resistance in Andean beans.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Lafoensia pacari represents an alternative to control phytopathogens and common bean (Phaseolus vulgaris L.) diseases. This study aimed to investigate the chemical composition of L. pacari ...phenolics-containing extract obtained from leaves and assess its in vitro and in vivo inhibitory activity against Curtobacterium flaccumfaciens pv. flaccumfaciens, Xanthomonas axonopodis pv. phaseoli, Xanthomonas fuscans subsp. fuscans,Xanthomonas sp., Colletotrichum lindemuthianum, Fusarium oxysporum and Macrophomina phaseolina. The microbial susceptibility screening and the extract’s potential to reduce the anthracnose severity and the common bacterial blight were examined. Eleven phenolic compounds were identified, eight of which were described for the first time in L. pacari leaves: gentisic, caffeic, p-coumaric, protocatechuic and vanillic acids, luteolin, naringenin and quercetin. The L. pacari extract completely inhibited bacterial growth at the concentration of 0.62-1.25 %, as well as the mycelial growth of the C. lindemuthianum (BRM 007626) isolate at the concentration of 5 % (v/v).Under greenhouse conditions, the extract led to the control of the common bacterial blight caused by X. axonopodis pv. phaseoli (BRM 25302) in the Pérola bean cultivar and to a low efficiency in the control of anthracnose caused by C. lindemuthianum (BRM 007447) in the IPA 7419 cultivar.
Symbiotic nitrogen fixing Rhizobium species have been reported to trigger induced resistance reactions that are inhibitive to aboveground antagonists. We tested the hypothesis that root infection by ...nitrogen-fixing Rhizobium triggers enzyme-mediated induced resistance reactions, which lead to the production of defensive compounds that suppress aboveground colonization by foliar pests. An experiment was conducted using common bean Phaseolus vulgaris, comprising of factorial treatments of Rhizobium inoculation (with or without), C. lindemuthianum (with or without) and soil type (solarized and non-solarized). Anthracnose disease incidence was higher in plants under dual inoculation with C. lindemuthianum and Rhizobium than in plants inoculated with C. lindemuthianum alone (p < 0.05). Concentrations of N-based compounds in the form of total protein and the enzymes, peroxidase, ascorbate peroxidase and lipid peroxidase were higher in rhizobial plants, while that of catalase enzyme and the C-based compounds namely flavonoids, tannins and phenols were lower. Plant size and growth duration were not different between the treatments (p > 0.05). Soil pH, organic carbon and the concentration of nutrients (N, P, Na, Ca, Mg, Zn, Cu) in solarized soil were higher than in non-solarized soil, while Fe and K were lower. There was no evidence to support induced resistance since anthracnose disease was high in Rhizobium inoculated plants. High disease incidence without reduction in plant growth can be interpreted as host plant tolerance. In conclusion, Rhizobium infection of common bean enhances the production of N-based nutritive compounds, while limiting the production of C-based organic compounds associated with plant resistance, thereby promoting host plant suitability to C. lindemuthianum, and possibly enhancing host plant tolerance to the pathogen.
•Rhizobium triggers enzyme-mediated induced resistance reactions.•Yet, anthracnose disease is high in rhizobial bean plants.•N-based compounds increase while C-based compounds decrease in rhizobial plants.•No evidence for induced resistance or plant growth suppression•Rhizobial plants are likely nutritively suitable but tolerant to C. lindemuthianum.
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